Piezoelectric ceramics and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-9647197-B2
Application number	US-201313926347-A
Country	US
Kind code	B2
Filing date	Jun 25, 2013
Priority date	Jul 26, 2012
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

There is provided a piezoelectric ceramics, including a perovskite compound of a non-stoichiometric composition represented by a composition formula (K x Na 1-x ) y (Nb 1-z Ta z )O 3 (0<x≦1, 0<y<1, 0≦z≦0.5); and a sintering aid which includes an oxide containing K, Co, and Ta.

First claim

What is claimed is:

1. A piezoelectric ceramic comprising:
a perovskite compound of a non-stoichiometric composition represented by a composition formula (K x Na 1-x ) y (Nb 1-z Ta z )O 3 (0<x≦1, 0<y<1, 0<z≦0.5); and
a sintering aid which includes an oxide containing K, Co, and Ta.

2. A piezoelectric ceramic comprising:
a perovskite compound of a non-stoichiometric composition represented by a composition formula (K x Na 1-x ) y (Nb 1-z Ta z )O 3 (0<x≦1, 0<y<1, 0≦z≦0.5); and
a sintering aid which includes an oxide containing K, Co, and Ta;
wherein, in the sintering aid, a molar ratio of K to a total number of moles of K, Co, and Ta is not more than four-thirteenths.

3. A piezoelectric ceramic comprising:
a perovskite compound of a non-stoichiometric composition represented by a composition formula (K x Na 1-x ) y (Nb 1-z Ta z )O 3 (0<x≦1, 0<y<1, 0≦z≦0.5); and
a sintering aid which includes an oxide containing K, Co, and Ta;
wherein, in the sintering aid, a molar ratio of Co to a total number of moles of K, Co, and Ta is not more than one-half.

4. The piezoelectric ceramic according to claim 3 ;
wherein, in the sintering aid, a molar ratio of Co to a total number of moles of K, Co, and Ta is not more than three-tenths.

5. The piezoelectric ceramic according to claim 1 ;
wherein, in the sintering aid, a molar ratio of Ta to a total number of moles of K, Co, and Ta is not less than three-tenths.

6. A method for manufacturing a piezoelectric ceramic, comprising:
preparing a main component to form a perovskite compound of a non-stoichiometric composition represented by a composition formula (K x Na 1-x ) y (Nb 1-z Ta z )O 3 (0<x≦1, 0<y<1, 0<z≦0.5);
preparing a sintering aid which includes an oxide containing K, Co, and Ta;
preparing a raw material mixture by blending the main component to form the perovskite compound of the non-stoichiometric composition and the sintering aid;
molding the raw material mixture in a predetermined shape; and
performing sintering of the molded raw material mixture.

7. The method for producing the piezoelectric ceramic according to claim 6 ;
wherein, in the sintering aid, a molar ratio of K to a total number of moles of K, Co, and Ta is not more than four-thirteenths.

8. The method for producing the piezoelectric ceramic according to claim 6 ;
wherein, in the sintering aid, a molar ratio of Co to a total number of moles of K, Co, and Ta is not more than one-half.

9. The method for producing the piezoelectric ceramic according to claim 6 ;
wherein, in the sintering aid, a molar ratio of Co to a total number of moles of K, Co, and Ta is not more than three-tenths.

10. The method for producing the piezoelectric ceramic according to claim 6 ;
wherein, in the sintering aid, a molar ratio of Ta to a total number of moles of K, Co, and Ta is not less than three-tenths.

Assignees

• Kikuta Koichi
• Isono Jun
• Kura Keiji
• Morita Yoshitsugu
• Nat Univ Corp Nagoya Univ

Inventors

• Kikuta Koichi
• Isono Jun
• Kura Keiji
• Morita Yoshitsugu

Classifications

• C01G33/006

  Compounds containing niobium, with or without oxygen or hydrogen, and containing two or more other elements · CPC title

• C04B2235/604

  Pressing at temperatures other than sintering temperatures · CPC title

• C04B2235/3201

  Alkali metal oxides or oxide-forming salts thereof · CPC title

• C01P2006/10

  Solid density · CPC title

• C04B35/62675

  characterised by the treatment temperature · CPC title